A pathogenic PSEN1 Trp165Cys mutation associated with early-onset Alzheimer's disease
Background Presenilin-1 (PSEN1) is one of the causative genes for early onset Alzheimer's disease (EOAD). Recently, emerging studies reported several novel PSEN1 mutations among Asian. We describe a male with EOAD had a pathogenic PSEN1 mutation. Case presentation A 53-year-old male presented with memory decline, followed by difficulty in finding ways. Patient had positive family history, since his mother and one of his brother was also affected with dementia. Brain magnetic resonance imaging (MRI) scan showed mild degree of atrophy of bilateral hippocampus and parietal lobe. 18F-Florbetaben-PET (FBB-PET) revealed increased amyloid deposition in bilateral frontal, parietal, temporal lobe and precuneus. Whole exome analysis revealed a heterozygous, probably pathogenic PSEN1 (c.695G > T, p.W165C) mutation. Interestingly, Trp165Cys mutation is located in trans membrane (TM)-III region, which is conserved between PSEN1/PSEN2. In vitro studies revealed that PSEN1 Trp165Cys could result in disturbances in amyloid metabolism. This prediction was confirmed by structure predictions and previous in vitro studies that the p.Trp165Cys could result in decreased Aβ42/Aβ40 ratios. Conclusion We report a case of EOAD having a pathogenic PSEN1 (Trp165Cys) confirmed with in silico and in vitro predictions. ; This work was supported by a National Research Foundation of Korea (NRF) Grants, awarded by the Korean government (MEST, No. 2017R1A2B4012636 & 2017R1C1B5017807). Dr. An SS receives the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST, No. 2017R1A2B4012636). Dr. Eva Bagyinszky receives the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST, No. 2017R1C1B5017807). Dr. Giau VV reports no disclosure. Dr. Pyun JM reports no disclosure. Dr. Suh J reports no disclosure. Dr. Kim SY reports no disclosure.
